This invention relates to fuel injectors used for injecting fuel to an internal combustion engine and more particularly, the invention relates to a method and apparatus used for delivering of fluid for cleaning carbon deposits, varnish and the like from fuel injectors.
When varnish or olefins become deposited in the fuel injector, it restricts the flow of fuel or changes the spray pattern detrimentally, interfering with engine performance. Thus, such materials must be removed to restore the engine to its original performance.
Many fuel injector cleaning devices have been suggested. However, current fuel injector cleaning systems require the disabling of the fuel pump and in many cases disconnecting the fuel supply and return line. Some systems require the removal of the injectors. This requires extensive time and special tools to accomplish and it often creates many unsafe conditions. Existing systems also require the vehicle to operate on chemicals in order to complete the cleaning process. In order to accomplish this, the cleaning chemicals must be diluted with gasoline or other fuels. This can severely reduce the effectiveness of the cleaning chemicals. Additionally, because of the complicated nature of existing mechanical assemblies, these current systems can require as many as 50-60 different parts to allow hookup to all of the different model vehicles. Finally, because some vehicles operate at extremely high fuel line pressures, this reduces the running time and the effectiveness of the cleaning operation.
U.S. Pat. No. 5,022,364, for example, discloses a method and apparatus for cleaning fuel injectors wherein the apparatus is connected to the fuel line remote from the engine compartment by removal of the fuel filter. However, in this method, the fuel line is disconnected but the fuel pump is not disconnected. Fuel is recirculated back to the fuel tank and the engine is run on the cleaning fluid. U.S. Pat. No, 5,271,361 discloses an engine conditioning apparatus and method to remove carbon deposits from fuel injectors by initially utilizing a priming pump to pump priming fuel to the engine from an external fuel source while the engine is being cranked for starting purposes. However, the engine fuel pump is then utilized to pump a combustible, carbon-removing conditioning fuel from the fuel source through the engine fuel system along a flow path that bypasses the priming pump. U.S. Pat. No. 5,287,834 discloses a method and apparatus for removing carbon deposits from fuel injectors by delivering fuel to the inlet of the engine fuel pump while the engine is cranked for starting purposes and then delivering an engine conditioning fuel which is a mixture of normal engine fuel and a carbon cleaning agent. U.S. Pat. No. 4,787,348 discloses a carbon-cleaning apparatus for diesel engines having an independent fuel-flow system including a diesel/chemical mixture fuel tank adapted to be interconnected to a diesel engine at the engine's fuel injection. An electronic control and monitoring system is used to operate the fuel-flow system during the cleaning operation of the engine. U.S. Pat. No. 4,784,170 discloses a fuel injector cleaning kit that includes a pressurized container containing fuel injector cleaning fluid and motor vehicle fuel. The kit includes instructions, hoses and adapters for connection to a plurality of different motor vehicles. Further, the kit includes a pressure regulator to control the pressure of the mixture delivered to the vehicle. Other cleaning devices and methods are disclosed in U.S. Pat. Nos. 4,606,311; 4,671,230; 4,807,578; 5,090,377; 5,097,806; 5,178,684; 5,289,837; 5,295,497 German reference 3832-338A; Japanese Kokai 52-4923A; Japanese reference 61-107987 and WO 92/14916.
In using prior devices, the fuel pump has to be disconnected or the fuel line from the fuel tank disconnected or similar operation which is both time consuming and presents a hazard from fuel spillage. Thus, it will be seen that there is a great need for fuel injector apparatus that is efficiently adaptable to any vehicle and does not require disconnecting fuel line or fuel pump.
The present invention provides such an apparatus.